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- Tutorial 6. 2D Graphics
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- This Tutorial shows how to do 2d graphics with the Irrlicht Engine. - It shows how to draw images, keycolor based sprites, transparent rectangles - and different fonts. You will may consider this useful if you want to - make a 2d game with the engine, or if you want to draw a cool interface - or head up display for your 3d game. -The program which is described here will look like this: -
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- Lets start! |
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- As always, I include the header files, use the irr namespace, and tell - the linker to link with the .lib file. -
At first, we let the user select the driver type, then start up the - engine, set a caption, and get a pointer to the video driver. -
All 2d graphics in this example are put together into one texture, - 2ddemo.bmp. Because we want to draw colorkey based sprites, we need - to load this texture and tell the engine, which part of it should be - transparent based on a colorkey. In this example, we don't tell it the - color directly, we just say "Hey Irrlicht Engine, you'll find the - color I want at position (0,0) on the texture.". Instead, it would - be also possible to call driver->makeColorKeyTexture(images, - video::SColor(0,0,0,0)), to make e.g. all black pixels transparent. - Please note, that makeColorKeyTexture just creates an alpha channel - based on the color. -
To be able to draw some text with two different fonts, we load them.
- Ok, we load just one, as first font we just use the default font which
- is built into the engine.
Everything is prepared, now we can draw everything in the draw loop, - between the begin scene and end scene calls. In this example, we are - just doing 2d graphics, but it would be no problem to mix them with - 3d graphics. Just try it out, and draw some 3d vertices or set up a - scene with the scene manager and draw it. -
First, we draw 3 sprites, using the alpha channel we created with makeColorKeyTexture. - The last parameter specifiys that the drawing method should use thiw alpha - channel. The parameter before the last one specifies a color, with wich - the sprite should be colored. (255,255,255,255) is full white, so the - sprite will look like the original. The third sprite is drawed colored - based on the time. -
Drawing text is really simple. The code should be self explanatory. -
At last, we draw the Irrlicht Engine logo (without using a color or an - alpha channel) and a transparent 2d Rectangle at the position of the mouse - cursor. -
That's all, it was not really difficult, I hope. -
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+ Tutorial 6. 2D Graphics
+ |
+
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+
+
+ This Tutorial shows how to do 2d graphics with the Irrlicht Engine. + It shows how to draw images, keycolor based sprites, transparent rectangles + and different fonts. You will may consider this useful if you want to + make a 2d game with the engine, or if you want to draw a cool interface + or head up display for your 3d game. +The program which is described here will look like this: +
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+ |
+
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+ Lets start! |
+ |||||||||
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+
+ As always, I include the header files, use the irr namespace, and tell + the linker to link with the .lib file. +
At first, we let the user select the driver type, then start up the + engine, set a caption, and get a pointer to the video driver. +
All 2d graphics in this example are put together into one texture, + 2ddemo.bmp. Because we want to draw colorkey based sprites, we need + to load this texture and tell the engine, which part of it should be + transparent based on a colorkey. In this example, we don't tell it the + color directly, we just say "Hey Irrlicht Engine, you'll find the + color I want at position (0,0) on the texture.". Instead, it would + be also possible to call driver->makeColorKeyTexture(images, + video::SColor(0,0,0,0)), to make e.g. all black pixels transparent. + Please note, that makeColorKeyTexture just creates an alpha channel + based on the color. +
To be able to draw some text with two different fonts, we load them.
+ Ok, we load just one, as first font we just use the default font which
+ is built into the engine.
Everything is prepared, now we can draw everything in the draw loop, + between the begin scene and end scene calls. In this example, we are + just doing 2d graphics, but it would be no problem to mix them with + 3d graphics. Just try it out, and draw some 3d vertices or set up a + scene with the scene manager and draw it. +
First, we draw 3 sprites, using the alpha channel we created with makeColorKeyTexture. + The last parameter specifiys that the drawing method should use thiw alpha + channel. The parameter before the last one specifies a color, with wich + the sprite should be colored. (255,255,255,255) is full white, so the + sprite will look like the original. The third sprite is drawed colored + based on the time. +
Drawing text is really simple. The code should be self explanatory. +
At last, we draw the Irrlicht Engine logo (without using a color or an + alpha channel) and a transparent 2d Rectangle at the position of the mouse + cursor. +
That's all, it was not really difficult, I hope. +
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+ + -- cgit v1.1